The use of paint stripes on road surfaces is the accepted method to indicate vehicle lanes, crossing lanes, parking areas and numerous other indicators. Various pavement marking techniques are well known in the art, including the use of traffic paint, thermoplastics, epoxy paints and preformed tapes. Most pavement marking systems are intended to be as durable and permanent as possible, and resistant to weathering and wear from traffic. Common road surfaces are asphalt and concrete. The removal of such striping is typically required when the road is to be resurfaced or if the indication is to be changed.
When polymers such as paint or plastic are used for roadway marking, the surface of the pavement is penetrated from ⅛-⅜ inch, so that mere surface removal of the marking material is not sufficient to remove the marking. Therefore, current pavement marking removal machines often employ various forms of cutting devices to remove the marking material, as well as a portion of the underlying layer of pavement material in order to effectively remove painted lines.
Commonly known methods for removal of such markings typically include the use of abrasive grinding wheels, material removing cutters, or blasting of abrasive particles against the material to be removed. However, the use of these devices often results in undesirable grooves in the pavement surface.
For example, one type of cutting machine is disclosed in U.S. Pat. No. 5,236,278 known as “Road Pro” manufactured by Dickson Industries, Inc. This type of machine employs parallel passive shafts that extend between circular rotating end plates. Hardened steel star wheels are carried on the parallel passive shafts and these star wheels strike and abrade the pavement surface. While this type of device is effective for removal of markings, it often creates excessive heat which may melt thermoplastic materials causing equipment to gum up. Also, since markings may sometimes penetrate below the surface of the roadway, as in the case of an asphalt roadway, a portion of the pavement surface must be removed to remove the marking. This results in excessive debris, slower operating speeds and a grooved surface that must be repaired. The instant invention avoids these problems by employing a combination abrader and high pressure fluid nozzle to remove the markings without penetration of the surface of the roadway.
Another approach to pavement marking removal is the use of diamond saw blades or cutters arranged to make a dado cut. Still other types of machines use grinders or shot blast as described in U.S. Pat. Nos. 4,753,052; 4,376,358; 3,900,969; 4,336,671; 3,977,128 and 4,377,924. Unfortunately, these devices must remove a portion of the pavement material to effectively remove the marking, thereby leaving unsightly and potentially dangerous grooves in the pavement. They also generate a large amount of abraded dust and particulate matter from the road surface which is either dispersed into the air or remains along the road surface requiring further cleaning. The instant invention overcomes these problems by capturing all the dust and debris that is generated by the strip removal process. Since the invention removes the final amount of striping with high pressure liquid, there is no damage to the surface of the roadway.
It is also known in the prior art to utilize high-pressure water jets to remove markings from pavements. The instant inventor teaches a Stripe Removal Systems in U.S. patent application Ser. Nos. 10/884,643; 11/340,104 and 11/340,738, the contents of which are incorporated herein in their entirety. In addition, NLB Corporation markets a high pressure water jet system for removing paint from pavement under the name “STARJET”. BLASTERS Corporation markets a high pressure water device which is mounted on a truck similar to the STARJET device.
The most common problem associated with these prior art devices is the removal of a portion of the pavement material during removal of the markings. If the entire road surface was going to be paved afterwards, this would not present a problem. However, if the road surface or parking lot was not going to be subsequently paved these prior art systems would leave unsightly and potentially dangerous grooves in the road surface or pavement which would have to be repaired prior to its being open to traffic. This repair involves a timely and costly filling in of the grooves.
The use of high powered water jet systems to remove striping or paint from a roadway surface or parking lot overcomes the problem of abrading away the top layer of the roadway surface and leaving grooves. These systems use a very large amount of water to remove the striping. This water cannot be dumped along the road side and must be properly disposed of. This presents multiple problems. The downtime to send the contaminated water off for disposal and the cost of proper disposal. Also, these systems do not move very fast. They operate at approximately 7,000 ft per hour.
Therefore, what is needed in the art is a stripe removal system that is capable of efficiently removing striping and other markings without damage to the underlying surface. The system should remove the striping without damaging the underlying surface in the event that new striping is to be subsequently applied. Also, what is needed is a system which will not contaminate the environment by allowing abraded dust and particulate mater from the roadway to be released into the atmosphere or surroundings. In addition, the system should be capable of employing water to remove the striping efficiently without excessive disposal costs or downtime. Finally, the system should be capable of removing striping at surface speeds far in excess of those currently available.